Hypodermic injection apparatus



March 13, 1956 e. N. HEIN, JR 2,737,946

HYPODERMIC INJECTION APPARATUS Filed Sept. 1, 1949 4 Sheets-Sheet 1 INVEN TOR. 5 012 1% 17am, fi:

f/TTOR/VEYS March 13, 1956 G,.N. HEIN, JR

HYPODERMIC INJECTION APPARATUS 4 Sheets-Sheet 3 Filed Sept. 1, 1949 HTTORNE YS March 13, 1956 N. HElN, JR

HYPODERMIC INJECTION APPARATUS 4 Sheets-Sheet 4 Filed Sept. 1, 1949 NawINVENTOR. (Z? M Hm,

IITTU/PNEYS United S M i INJECTIONAPFARATUS George-N.-Hein; Jr., SanCarlos, Calif. Application September 1', 19 49, Serial Nr-113,598" 10Claims. (Cl: 121F173) This invention: relates to anapparatus forhypodermically. injecting medicaments and especially an" apparatus'whichexpels-the medicaments in a fine streamand as such velocities that ahypodermic injection is achieved without the use of askin-penetratingneedle;

In certain respects thepresent invention: embraces= a design: embodyingvfunctional andstructural improve ments over those disclosed in my priorapplication for United States Letters Patent on: Injection Assembly;filed on May 29, 194-8, and identified under Serial Number 30, 041,and-now abandonedi It' is a! primary object to furnish an apparatus ofthis type 7 which-ifit employs" operating: fluid such asliquid or!air'that fluid will be embraced in: a sealedsystem such that leakagewill be substantially preventeds- Ac cordingly" it Will not be necessaryto periodically service the apparatus to replace the fluid which mayhave escapedt More importantis the fact'tha't partialdrcornplete'operating failure of the" apparatus will not incident" tolosses of operating fluids;

Another object is that of providing a medicament chamber embodying. astructure under which I proper" slippoi't and ope'ration'of the-partswill'be achieves 're ard less of the type of" ampule employed.

Still another object is that of furnishing a structure includingrelatively few artseach individually sini le and rugged" in constructionandcapable' of quantity production' to furnish a relatively economicalunit Mereover; such parts vvlilhlie' capable of readyassei'nblage andwhenso assembled will provide a u'nitaryapparanis functioning over long'periods of tim'ewith freedoniffrorn all difii'cultie's; I

With: theseand other objects in mind reference is had to the attachedsheets of drawin'g's" illustrating f practical embodimentsof'the' jiwmnnan'd in' whicli:

Big; 1' is a'plan view'of'an injection? apparatus;

Fig: 3is alon'g'itudinal sectional"view;'.

Fig; 4" is a" transverse sectional view taken along the lines 4 4 a'nd'in the direction of the'arrows' asinnieateu in Fig-3E 1 Fig: 5" is" a"somewhat scli'ematic'view'sliowingiri en largecl section one form ofmedicament clia'thbei and the partsadja'cent thereto? I Fig. is'a' viewsimilar to' Fig.' 5 butshowin' attieaosition of the" parts" during" theexpulsion of medicament from" the chamber;

Fig. 7isla'sirriilar and sor'newhafschernatic view showinga structurealternative to that illustrated in 5 'a'nd '6";-

Fig; 8"is a' view similar to Fig. 3" but showing a dilferen'fassembly;

Fig. 9 isa fragmentary. elevation of a detail of the mechanism as shownin Fig.1 8}.

Fig: 10 is a transversesectional"view'taken. along lines 10 -10"and"inthe directionof the arrows as shown in Fig. 8'}

2,737,946 Patented Man 13', 1956 2 Fig; ll is a sectional end view' ofthe unit shown in Fig; 12'is' a fragmentary view of an alternative formofmedicament chamber;

Fig. 13 isa'sec'tional side view of an assemblywhich may be employed forcreating: the necessary mechanical force;

Fig; 14'is a view" similar to Fig. 8 butshowing a still further form ofstructure;

Fig 15 is" a transverse sectional view takeri along the lines 15= 15 andin the direction of the as indicate'din'Fig'; 14; and

Fig: 16 is an enlarged fragmentary sec'tibfial' view of a structureemploying a motivating spring"- assembly exert ing a; substantiallyuniform operating force;

By'means-or thepf'es'e'rifiinvent'ion an apparatus is furnished whieh;as afor'ebrought out, will primarily produce a hypodermic ejection ofmedicament witho'ut employing a" skin penetrating needle. The injectionwill occur from its initial toits final stage under" substantiallyconst'ant ressure conditions." The apparatus may repeatedly'used andwill have a long and effective life:

According to" one preferred aspect of themedicament chambcr'willinvolvea type of construction that a proper support will 'be' achieveddli'fing'tlie" entireex'p'iilsion of the" solution; The solutioncontaining. riieihber within that chamber may be" used;sterili'z'edifilled" ah'd re used any number" of time's;As"win'lierearter aepear, the medicament chamber receivesampules'whicliwill be supported against bursting" or" collapse; The'-details" of such preferred forms of chambers will be late? corisideredl'Referring primarily to theass'ei'nbly' as sho'wr'i in" 1 to "4, thenumeral 10 indicates a casin'g'whicli, asilliistrated, is preferablyelongated. This" casing supports adjacent one of its ends a loadingcap1'1;-which; for pur-.

poses'of" the present illustration,.-niaybe provided-with grippingextensions or wings 12; and be" retained in positi'on' by threads 131The cap Il defines the-outerend of an ampule receiving 'chamber' l4Theampule may talte oiieof numerous different forms. As-sliowmit-include s a flexible cup shap'ed container 1 5 which is preferably formed ofrubber; and provided-with an outer flange portiorf 1'6. Detachablyassociated with; the inwardly extending portion of flange 16 is; anozzle 17 which-defines arfinjectio'n orifice of relativelysrnall crosssectiom- For eziarr' plepit is on the order of from .015 to .005'2 I Thebody 15is received Wlt hllI'af tubular sleeve- 18. The latter may beformed of rubber similar-to the ampule or body-15. As shown sleeve 18isslightly tapered-and this tapering :has, for purposes of-illustration;been-somewhat exaggerated. 1 Actually it is a on 1 theorderof from 1%?to2. Sleeve 18 is supported bya collar 1-9: In common with body It] andcap 11- this collar is fo'rmed of metal.- A screw thread mounting;isprovided 'for'cap 11 and corresponding threads are formed" on theouter end of thecollar. Similar threads 20* may be'provided to connectthecollar withthe main part of body 10. In line-with-the inner endofthe-bore o'f sleeve lll collar 19 is formed withan openingwhiclf'perrnits of the slidable passage of a plunger 21'. To'veht'anyair whichm'ay be-trappedbemeen the base of the" ampule 'aritlthe outei' end of plunger 21, the latter is provided with a-passageli.The'plunger2lis-as shown'integr al witha nieriibefifl which-maybe termeda piston. This member ispfeventea fromrturning with 'respectto bodyIObyagioove aiid 'p'in structure 24. Member 23 is hollow and thusprbvids a chamber 25 which: airs-hereafter described =functiori' as anaccumulator and fluid pressure chamber; Thereat end ofthischamberissealed-by ahexibleunit 26 which is again convenientlyformed of rubber and comprises a 3 generally cup-shaped unit invertedupon itself. A leakproof seal is furnished between the unit 26 and theslidable member or piston 23 by having the former provided with a flange27 which seats against a cooperating flange 28 which is part of thelatter. A washer 29 may bear against the outer face of flange 27 and theassembly is maintained with its faces in firm contact by utilizing atube 30 which has, at its inner end, threads 31 cooperating with similarthreads formed on the inner face of member 23 adjacent its rear end.

A piston 32 is slidably mounted within tube 30 and by means of a groove33 and a cooperating projection 34 is restrained against rotation withrespect to the tube. The rear end of the bore of this tube is formedwith lands to restrict the outward movement of this piston. The latteris formed with a threaded recess 35 within which the end of acorrespondingly threaded stem 36 projects. To the rear of this threadedportion the stem is preferably enlarged and formed with oppositelyextending threads 37. These engage with corresponding threads formed ina cap 38 secured to body 10. The stem mounts at a point beyond the rearof this body an actuating member .which conveniently takes the form of apair of wings 39 which may readily be grasped by the user. It istherefore apparent that by grasping body with one hand and the actuator39 with the other, the stem may be turned to cause a projection orretraction of piston 32.

In order to provide a latch or releasing structure body 10 supports onits outer face a mounting 4-0. The latter,

by a pivot 41, serves to rockingly mount a lever 42 provided with anextension 43. A dog or pawl 44 is also pivotally supported by mounting40 as at 45. A safety is furnished by having mounting 40 rotatably carrya shaft 47 which may be notched or ground down as indicated in Fig. 3.This shaft underlies lever 42 and has secured to it an operatingextension 48. The mounting 40 may be provided with symbols indicating,for example, 'Safe and Fire between which the extension may be swung.When that extension is in the position shown in Fig. 2 then shaft 47will prevent any inward movement of lever 42. When the extension is inthe position shown in Figure 3, the notched or relatively reduced partof shaft 47 will underlie lever 42 and the latter may be swung inwardly.A spring 49 is also conveniently supported by mounting 40 and has itsopposite ends bearing against lever 42 and the dog or pawl 44 to urgethem in opposite directions.

A stop cooperative with the pawl 44 is furnished by mounting a nut 50upon threads which are formed upon 'the exterior face of tube 30. Thisnut conveniently has 'a forward or beveled face which may be engaged bythe adjacent face of pawl 44; the latter being held against movement bythe locking extension 43 of lever 42. The

the space intervening the layers of element 26 is filled with a suitablelubricant indicated at 53 and which includes graphite.

The threads on stem 36 should, of course, be suitably lubricated. Theaccumulator chamber will be charged with fluid under pressure. Suchfluid may conveniently be nitrogen under suitable pressure (for example,1200 to 5000 lbs. per sq. in.). With the safety in position, loading cap11 is removed and an ampule is disposed within the medicament-containingchamber.

The cap is re-applied and nozzle 17 will extend beyond the end of thesame. Now by effecting relative turning of body 10 with respect to theactuator 39, piston 32 will be projected and will tend to carry with ittube 30. If collar 50 is adjusted to an extreme position as shown inFigs. 2 and 3 and aligns with graduation 54 on casing 10, then anytendency of tube 30 to thus move will be prevented because of theimmediate engagement of collar 50 with pawl 44. Under thesecircumstances, piston 32 will simply move inwardly of accumulatorchamber 25 coutaining the operating fluid and will serve to compress thebody of that fluid to an extent greater than its initial compression. Acontinuation of this operation will result in piston 32 being fullyprojected. At that point flexible element 26 may no longer be invertedupon itself but merely extend inwardly in the form of a closed tube.Under these circumstances, forward movement of member 23 is preventedincident to the engagement of dog or pawl 44 with the collar or nut 50.

Nozzle 17 is now disposed adjacent the tissue to be penetrated. Thesafety is released. Upon lever 42 being swung, the locking extension 43thereof moves beyond the adjacent face of pawl 44. The surface of thelatter, in engagement with collar 50, will now cam against the action ofspring 49. Therefore, member 23 will be released so that its plunger 21may move against the base of ampule 15 and collapse or invert thelatter'to eject the solution contained therein through the orifice ofnozzle 17. This will result in the desired injection. With the forwardmovement of member 23 element 53 will again assume an inverted position.In other words it would be inverted upon itself. This will be becausemember 23 will move while projecting member 32 remains stationary. Thebase of the cup is carried by the latter while the flange portionthereof is carried by member 23. Assuming that medicament chamber 14 hasa capacity of 1 cc., then the graduations 52 may each define one-fifthof 1 cc. By turning actuator 39 with respect to the body to where one ofmore of these graduations align with graduation 52, a correspondingdosage will be ejected from the medicament chamber. Likewise byadjusting collar 50 along the threads which mount it, a desired amountof the fluid dosage will be ejected. It is obvious that the foregoingvolumes are only illustrative and that the capacity of the device mightbe greater or less than 1 cc.

With the unit charged a reverse turning of the actuator 39 with respectto body 10 will cause piston 32 to be retracted. Plunger 21 will also bewithdrawn from the medicament chamber. The loading cap 11 may thereuponbe dismounted, and the spent ampule discarded or refilled. In any event,with an ampule in position, the entire operation may be repeated; itbeing understood that with the retraction of the piston, dog or pawl 44will, under the influence of spring 49, reassume a position in which itis locked against movement.

Now referring to Figs. 5 and 6 a detailed showing of the assemblyproviding the medicament chamber has been illustrated. Supported withinthe latter is an ampulc formed of flexible, solid rubber which isrelatively soft. Intel-posed between this unit and the exterior metallicwalls of the assembly is a layer 82 of relatively softer rubbercorresponding to sleeve 18. This should be free of air pockets or, inother words, be solid. ,As shown, the cup 83 adjacent its outer flangeis thickened.

With an assembly such as this, if the plunger 21 is projected, thesurface of cup 15 will, in effect, be peeled out of contact with thesurface of layer or sleeve 82. This action has been shown in Fig. 6 andit will be understood that it will occur with little or no chafing orfriction taking place between the layers and will continue as theplunger advances. That portion of the cup beyond its base will displaceoutwardly in sleeve 82, incident to the cup inverting, and immediatelyfills in the space short of the cup base as the inverting action iscontinued. As will be appreciated, with the advance of plunger 21, thecup expands radially Therefore, this displaced rubber prevents the sackfrom distending rearwardly and for cooperation, with themedicamentchamber.

"the valve.

seashore from being subjeeted to undue stress or strain. l'n'efictlayer. 82 urges the material ofi'the' cup fbrwardly due to theperistaltic-like action whichv occurs" incident to the medieamenvpressure within the cup. Inthisrespect it will be understood that theinner surfacezof the cupis not* alonesupported by the medicament"pressure as plunger" 21 advances,- but it isalso lubricated thereby;

As atpresent visualized, the medicament chamber assembly may preferablyembrace a structure as iir Fi'gs. 5' and 6'i It is apparent; however;that-other assemblies might also be employed and" in certain instancesthese might even include aprovision-fbr elm-external support of anyampule or similar unit disposed in the medicament chamber; In-thisconnection and as shown iinFigz 7, the outer end of the unit isdefined"by a: sleeve: 84 of suitable rubber in' sea-ling contact with the outercasing. Encircling'thesleeve' is a-body 85-of liquid. T he sleevereceives a cup sucli as. with" which the" pliln'ger 21 cooperates.

It is obvious in this form of construction that as plunger 21* advancescup 15 Will be inverted: Incident to this action portions of sleeve 84will be displacedi The liquid 85 being substantially incompressible: it'follows that with=this "displacement'an inward or 'supporting'pressurewill be exerted by- 'the' forward portions of' the sleve againstthoseportions of thecapwhich=are stilltfiiled withmedicament: Accordingly,while it' is preferred that cup 15 directly contain themedicament it: isapparent that ifit should enclose an: ampule; the latter willihesupported againsr bursting should such a result bendesired. Also asheretofore described,'i-the-fluid medicament will act to lubricat'ethe'adjacent surfaces of! the cup 15? as'the latter inverts F and -.peelsoutoft contact with 8166316 841 Now referringto thestructures-shownin:Figs;.8 toill inclusive,- it will be observeclthattthe numeral? 86' indicat'es the outer casing. SwingingIyconnected'to thcilatter by a loose pivot coupling. 87-" is a1 cap' 88:which. defines the-medicamentchambe11 A's heretofore described-thelatter mounts a: rubber sleevedefiningmspacet suitable ion the 1reception" of a medicament: containing cup with which anozzleiszassociated: A. securing'iring'sik'isirotatably coupleditotcap88: As shown; espeoia'llyiinrEig. 1L1 .this cap and: the:a'djacentisurface ofbodyr 86 isrformed with interrupted threads 90.Accordinglyrby bringing theparts' to positions adjacent: each: other.and merely rotating them through an arc" of ap proximately! 90? they mayhe firmly secured against movement; Conversely byeffecting a relativerotation=of 'the'same in' aDZ OPPOSiK direction thezcap may be-freed-to'swin'g around-pivot -8'7. Whensoswung access may be had to themedicament chamber for removing theexhausted cupor equivalentpart'therefiom andrepla'cing'it with a fresh-unit:

Slidably mountedwithin body '86is;a hollow member .91'the.forward end ofwhich terminates. ina plunger 92 This plunger is.formed withiatransverse, bore-93 in addition to :alongitudinal bore 94, Communication.betweenthese boresand the interiorofi member. 91=isinorma1ly presvented by employingaasuitablewalve assembly The latter: includesastem 95terminatingin an inward head 96::aznd havingsarvent groove-19.7;Asspring= 98= urgesestem 953111381110111Wfl1d direction .tandia washerof rubber. 99 is mounted'lby this stem=and partially-"enclosedcby 'cap96 to thus normally prevent-anyhow of fluidthrough groove 97.If;.for*discharge-purposes, such flow-'istobeinititated; thenbyinserting a suitable instrument through bore'93 a' thrusrmay'beexertedon stem 95 toallowof an escape of'fiuid. Conversely, if theinterior otmember91is'to be chargedwith, for example; nitrogen under asuitable pressure; then; by employingaproper" fitting which is broughtinto operative relationship" with the bore of plunger 92 a charging'flow may be achieved past With the completion of" suchcharging'thevalvewill return toseatedp ositionto prevent any escape of the gas fromthe interior of 'member" 91L Secured against rotation with respect" tothis member i'sa sleeve 100. Theforward' end of the latteris clb'sedexcept fora relatively small passage- 101 This sleeve providesw borefunctioning as a' cylinder 102 which" is filled with grease; oil or'other displaceable material. A piston 103" extends into this here and asuitable" O-ring packing; 104 may beprovidedbetween the piston andcylinder-to prevent an'es'cape'of thedisplaceable material. The pistonisformed with a threaded bore'105' within whichtheinner end ofa threadedplunger 106 extends; The outer end 5 of this plunger is oppositelythreaded and bears against the thread's' of a closure plug 107: Securedto the rear end" of plimger 106- are operating surfaces whichtakestheformof' wings 108 corresp'onding' tothe structureheretoforedescribed in' Figs. 1 to 4' inclusive. Aisofin common withthafstructure graduations 10'9 are provided to indicate the operativecapacity to Whichthe partshavebcen'adjusted? The rear endof piston103,is encircled bya collar 110 which is provided'with a-land I11 andgroove 112 for cooperation'with outwardly'extending guiding portion 113forming a part of pistonl'tBi '(follarllfl isalso formed withone or'more longitudinally extending grooves'114withinwhich the inner end' of asetscrewTlErides for preventing a turning of'the collar.

A' releasable latch structure is furnished by having the coliar'formedwith'a shoulder 116' which cooperates with the end of'a-latch. Lever 117is pivoted" as at 118 and normally maintained in seated'position byaspring. The outer-face of casing '86" mount'sa guide'unit 119which hasits'outer'face'l'zfl extending inan inclined plane. A" car'- riage'lflisrecipro'cable'in the guide unit and" supports a cap 122". The lattermounts apin'123"which'engages' the ihner-end of' lever 117; By'means'of-a loose connection clfi'ned' by a-pih-124 and'a slot 125;cap122" iscouple'd to a nut 1'26"; additional: guiding" means being alsopref erabl'yemployed between these elements; The*nut'rides onthetiirea'ded stem'12.7 which; at its lower end, terminatesinthe'carriagelzlt As *shown, rotation retard ing means such as aspring is employed to prevent a free or accidental-movement of cap 122with" respect-tonut 126'; Also as shown, especially-in Fig; 9, slot1'25'has -one reducedend portion conveniently identified'by'the letter Sand asomewhat'enl arged or flared opposite-endporti'on convenientlyidentified by" the letter F. These identifications" may*designate Fireand Safe respectively. Finally, asshownimFig; 8, an'inverted sack'12'8preferably ofrubber, has its ends'anchored against the escape of fiuids'fromwithin the* body ofmemb'er 91'; its base portiomdfi'niirg a barrieragainst E the entrance'to the'body'of grease, oil; orotheroperatingliquid within chamber 102- and the=spacebetween the-endwall'o'f sleeve 100 and the interior 'of'member912 Cbnsidering' theoperation" of the mechanism as illus trated and'de'scribed inconnectionwith'Fi'gs. 8'to-11' it will be assumed that the medicamentchamberis" filled and that'th'e-interior of member 91 is chargedwith airor gas under'pressure. Thepreferred method of so charging'has beenpreviously described' and' the=value of the charge'may be on theorder-of 1500 pounds per square inch; It will'moreover be assumedthatthe displaceable material"102 is in position. Under'thesecircumstancesit will'be appreciated that this'material will beundera'nequal'degree' of pressure and will'therefore react against packing 104so that an effctive'seal isfurnished." In this connection it"will beunderstood due to the 'fact that the material is-under suchinitialpressurethat'the-packing is under-a correspondingly highpressure. Thereforeseep age'or' leakage'will be reduced to aminimum:Withthe capacity of'the medicament chamber being 1 cc; and itbeingdesired to inject the entire" capacity of thischamber;the-procedure will 'be' as'follows:

Carriage-121 willbeshifted to the left to'its extreme positionasshown'in'Fig. 11L IllSLlCh'IIlOVCIIIflIlt member 91' will becorrespondinglyshifted" to retract-the -pll'mger 92 so that cap 88 maybe secured by rotating ring 89. Of course before carriage 121 is shiftedto the left, cap 122 will be rotated in a counter-clockwise direction tocause nut 126 to be elevated to free the carriage 121. With the parts soshifted, cap 122 will be tightened or as shown rotated in a clockwisedirection. This will cause pin 124 to initially ride into the reducedend portion of slot 125 and thereupon will cause nut .126 to ride downstem 127 to clamp carriage 121 against movement. Stern 106 is nowrotated to project piston 103. Under these circumstances, carriage 121will not shift even though cap 122 has been tightened by merely grippingthe same with the fingers and turning it in clockwise direction withreasonable force. This will be because any tendency of carriage 121 tomove to the right as viewed in Fig. 11 will immediately result in theestablishment of a wedging action incident to contact with surface 120.Therefore, the projection of stem 1113 may be continued up to the limitof its movement.

With such projection the material 102 will be displaced through opening101 and cause sack 128 to be distended mainly by moving the base portionof the sack inwardly of the chamber defined by member 91. Under thesecircumstances the pressure of the gas within that chamber will beincreased. The nozzle may now be disposed in a position overlying thetissues to be injected. By turning cap 122 in a counter-clockwisedirection, the parts are shifted from a Safe to a Firing position.Therefore, if cap 1.22 is pressed inwardly, stern 123 will be projectedto rock lever 117 to a position at which it clears shoulder 116. Underthese circumstances, member 91 will project carrying with it plunger 92which will cooperate with the medicament chamber in the manneraforedescribed to expel the solution in a sufiiciently fine stream andat velocities and under pressures such that the desired hypodermicinjection will be etfected. Thereafter, piston 103 may be retracted, cap88 may be released and the exhausted cup removed and replaced by a freshcup or ampule. In common with the structures heretofore and hereafterdescribed, this element may be sterilized and refilled for future use.

Of course if a full injection of 1 cc. is not desired, then it isapparent that, as before described, stem 113 may be rotated by the Wings108 or otherwise so as to be only partly projected. The degree of suchprojection will be indicated by the scale marks or other indicia 109. Inthe event it is desired to employ a rupturable ampule as the medicamentcontainer, the structure as disclosed in Fig. 12 may be employed. Inthat view, numeral 128 indicates the projectible plunger and 129 theparts of the assembly which define the medicament chamber. in the lattera container 130 formed, for example, of tin or gelatin is disposed.Beyond this, a nozzle 131 is mounted and the outer end of which willdefine an orifice of suffieiently reduced diameter to provide thedesired fluid jet. The base of this nozzle is formed with a recess 132,one edge of which is rounded as at 133. Therefore, the plunger 128 whichprojects the solution within container or ampule 130 will be placedunder pressure. The rounded surface 133 of recess 132 will furnish aguide such that as the pressure increases the body of container 130 willrupture or sever along the relatively sharp edge defining the inner endof recess 132 and will hinge or fold over surface 133. Therefore, a flapwill be provided incident to the rupturing and no fragments will bepresent which will lodge within the bore of the nozzle or other- -wiseinterfere with the proper operation of the device.

after described. It is to be understood, however, that the apparatusherein disclosed is primarily intended for in jections of the velocitytype rather than for employment with a skin penetrating needle and theillustration under numeral 134 is therefor merely suggestive of thepossible use of the apparatus.

As in Figs. 1 to 4 the motive force depended upon for operation of theassembly is purely air or gas under pressure. In Figs. 8 to 11 gas underpressure and hydraulic operating liquid system is included. Undercertain circumstances it might be desired to employ a structure in whichno gas accumulator is present. In such an event, a mechanism asillustrated in Fig. 13 might be utilized.

In that view the numeral 135 identifies the member corresponding tomember 91. This member is provided with a plunger 136 which is formedwith a venting bore 137. A spring 138 is disposed within the member andhas its forward end bearing against the inner face of the end wall ofthat member. A collar 139 is disposed adjacent the rear end of themember and a backing ring 140 is arranged beyond this collar to confinethe spring. A threaded bore 141 forms a part of collar 139 and isengaged by the threads of a stem as shown and described in connectionwith Fig. 11. Member 135 may be formed with an opening to define an edge142 which acts as a stop shoulder similar to shoulder 116 and with whichthe end of a lever 117 cooperates. Also it is formed with an opening 143within which a pin 144 rides to restrain the member against rotation.That pin or screw would serve the same function as the groove 114 andthe screw 115 of Fig. 8.

It is obvious that with a structure as shown in Fig. 13, a rotation ofthe stem would result in a cocking of the apparatus as previouslydescribed. Also a shifting of lever 117 would release member 135 and itsplunger 136 so that it would project to expel the medicament from itschamber. Due to the provision of bore 137 any air entrapped between thebase of the medicament chamber and the end of the plunger would bevented. Allowing for these differences in detail, the apparatus wouldfunction precisely in the manner described in the earlier figures,excepting that the pretensioned spring 138 would make it unnecessary toutilize an accumulator system in which gasses or gasses and liquid wouldbe confined under high pressures.

Now referring to the assembly shown especially in Fig. 14 it will beobserved that the numeral 144 indicates the main casing of the deviceand 145 a mounting extending therefrom and beyond which there projects acap 146. Inwardly of this mounting a pivoted lever 147 is disposed.These parts correspond to the similar parts heretofore described in Fig.8. In common with the structure in the earlier figure, a scale 149appears upon the outer face of mounting 145 and is traversed by asuitable indicating mark associated with the carriage. A cap 149 closesthe outer end of the medicament chamber within which a cup 150 isdisposed Within a lining sleeve 151 of relatively soft, displaceablerubber. The sleeve itself is anchored against displacement within acollar 152 and the inner end of the sleeve conveniently embraces a zone153 of relatively hard rubber.

Contrary to the constructions heretofore described, the base of cup 150is formed with an opening. Extending into the latter is a bored stem154. The inner end of that bore is continued in the form of a cannula155 terminating in a point and preferably mounting upon its shank acollar or spacing member 156. A cap 157 is conveniently snapped ontostem 154 and covers the inner face of the latter. This cap is formedwith a suitable number of perforations 158. The diameter of the latter,as well as the bore of the cannula, should be substantially in excess ofthe jet-defining orifice of the nozzle associated with the outer end ofcup 150.

The plunger 159 is formed with a bore 160, the outer end of which isthreaded to cooperate with the threads 161 oi storm I. The outenend of'bore'lfilllis surfle'edismas to genera llyconform-to the adjacent faees154.1 Thediameter of 'b'ore 1'60' issuch" that ittwi-lbaccommodate thespacing member- 156% A projeetible; member162lis preferably integralwith stern- 1'59 and houses. auspring 163' which is" under initialcompression'. Member 162 is convenientlyi. formed aslot lfiitdefiningarear'shoulder functioning as a stop in cooperation with lever 147. Aswill be observed, the conuoliltions oft spring; 163' define: :a space:This space is ample: in aareattoi accommodate a medicament-containingampule;

Suchaamampuletconveniently formed' of glass' has been indicated at 165:'Iherrear end-of theampule is closed hyra: stopper 1661 which:conveniently presents upon its outer:facezaicentrallwperforated disk167. The inner end of athee ampulesisuclosed lby'a stopper or cap 168fbrmedz with as bore. 169whiclrz extends into its nose 170., The:inner-end of bore' 160'" is surfaced to: conformr to: this: nose:portion It will be; observed that tthe-,lengthlof"the cannula 155 issuch' that 'withathe partssdisposedoin the manner: shown in-Fig'. 14,itspoi-nted innerrend willtpiercel the endi of nose portion 170 andlodgecwithinzthe bore-x169.

Adjacenttthetear end of casing 144: a stern- 171 is disposed; This stemihassoppositelw extending threads as inztheecasesofzthe :stems-ofearlier:- described formss The threadszarijaeent thesinnenend'ofthis'stemacooperate with the threads of a collar 172 convenientlyhaving: outstandingz'ribs onspiinese173 i -riding within-grooves formedimaasleeveelfld. Atpinz175 lextends transversely-of and an; opening imcollara172L A set screw 176 projects beyond;:tlie casings-144 andhas-engagement with therthreads a'tbbrmformed through sleevew174? Theinner end: of; this set: screw extends into a groove 17 7formed-zinzcollar 172: Atplug 178iis -mounted by=the rear end-lofgbbdylfl'iby,lfor example; a ring 179 and is presented"; from rotating witharespect to: casing 144. Wings: or other; suitable: manipulating portions18(Vare SBCll-ICdEIO? stem? 131 so: thatzit'ma 1 bezturnedi These wingsare: spaced; and the. stem isformed with=aa bore such 1111211 agraduated. pusher rod 181" may be= inserted into. thesinteriorx ofzthecasings. and. disposed in- I operative relationship with.thezstopperr166.

Astwilhbe apparenti pin: 17 preventscollar "172 from rotatingwithlrespecttplugs178e. However; this-collar maybm-projectedzlandxretracted byrrotation' ofi stem 171. Withtsuchshiftingit is; apparent -:that therprojecing portionsi- 1732 will; bean against.therreary'end: of: springr163 so tthat .this;spring;willlbeecompressed:to. an: even: greater extent. Therefore,withtoperationofzlatcliustructure member' 162;-,together withitspplunger: 159 may betprojectedtin order, to invert the; cup 15.0:andvexpel medicamenti therefromtl or s to. otherwise coach with r themedicament: .containinggchamber; in; order. to etfectasueh expulsion.

Ihoperatingvthis mnittthe cocking assembly-is..primarily removed. Thatassembly will-fiincluderthe-l plug: 17 8;. the stem.-171,,the1ring1791and collar=172.. The zfilledtampule l.65 may 'nowbezdisposed-inposition. So positionedzits inner end willlbear; againstthe end Wall of. member; 16.2 and. thelnose portion170lof,stopper.168.will bear against the adjacent surfaces ofl'borel,160 'ofplunger-159. With cap 149 removed; cup 150'may be insertedintothe space defined by backing sleeve 1511 The operator will.use careto'introdirce' cannula 155"into bore 1'60'fand to engage'tliread161ofplug154 with the thread'of that bore.

is imerted..througl;t.,the-:bore: ofzstemczfll; itssredueed end 10 Willicenter imthm aperture or recess of 'diskt 1&7? Con tinued'i projection:of rod? 181 will I shift I stopper lfie" irrwardly. Accordinglytliedatterwill' funetion as a piston to expel medicament 1 throughbore169 and the :boremf the needleorcannula past the valvestructureprovidedby the adjacent surfaces of stemz154 and cap 157 and into the medieamentchamber If theunit istherefore held a substantially upright position,this actionma y be continued' until 1 medicament completely fills-thecup or chann ber' 15d: and? flows through the= orifice of the nozzleassociated therewith; The operatorwill nowknow that' thechamberischarged; Assuming thecapacityof the latter to be 1' cc: andth'e rod 181 to have been projected to' a corresponding extent asevidencedlby the graduations 'carried by that trod; then the latch"actuatingcara -146 may-"be turned in" a.clock wise di rection aswviewedin Figs 14. Thereupon that cap will be tightened as aforedescribed andthe entire apparatus will be on-'Safe "position; With the cookingassembly. properly mounted by" casing 144 actuator' 180:: may now beturned;- This: will result in the pretensioned spring 163beingcompressed to an adequate extent. Thereupon; by" operating'thereleasecap1"46 as aforedescribed the? desired projection maybe" achieved. In tsuch :projection; a return flow 'of liquid f frorn the cup 1510i intothe-reservoir: or ampule 165is prevented' 'b'y tlie eheckzvalvestructure afforded by cap 157 "in cooperation withutheasurface'ofsstem154 and=in view ofth'e =fact that theiperforationsi1158 of the cap-arenotaligned' with'the adjacent end of the passage between thereservoir-ampule andi thmmedicamentf chamber; Subsequentinjections maybeaccomplishedtby 'simply re-cocking the cocking mechanism, shiftingmember 162 rearwardly, locking the parts byrturningthe cap andfth'ereupon"projecting-rod 181 aforedescribedi This willragain fill themedicament chamhenandlthe cocking 'mechanism will again be operated'.With thespartszproportioned in the manner sliown thetampulezlfiS: will:holdiapproximately eight charges of 11cc; 68.6fm Thereforeceightsuccessive operations 0f-the apparatus smaysxbezaccomplishedi before it;is necessaryto again: remove the. packing assembly; withdraw theexhaustedr'ampuleclfiitand reload the apparatus;

Binally,*.referring2to Fig; 16; it will be seen that the numeral 182indicatesithernain' casing of thelapparatus with theaouterrendrofwhich-ra loading cap 185 maybe-associated; The medicament chamber atthat'outen end may contain:a:cup:-186':as*heretofore described a-nd"which is capable .of inversion within a layer or sleeve of" relatively'softzrubb'eri A nozzle is'-associated With the cup. A plunger'l8'7'firrthe form of. a tube cooperates with-the basenof there-up: and'ia rodll88is slidably disposed within the.= bore: of tube: 1873' Cam surfaces 189maytorm a part :ofirodilBBl'and cooperate withradially extending rods19!! whichthavecat theirv'outeriends brake-surfacing' materialz191rcooperating: with the inner face of' casing liiz.

Atmember 18atis islidably mounted in E that casing-andhaszdisposediawithin'. it'a .pre-loaded lrnain spring 184. A timepprtiomlB-ZZmay extend rearwardly' from ttlie' outer endswallofmember:183 and house-a pressure-regulating springz193-actii1g upon:the base of rodl88i An-adii1stment'screwr194 mayserve to tension; to agreaternr lesser extent, springs-193i Atl'th is time it=is tobe observedthat the:conyolutionssoftthetlatterspring are spaced a distance suchthattit wouldzdefi'nitely limit inward movement of rod 188. If otherstopzmeans are desirable, thenthey mayl be employed? ins-lieu: of :thisconvolution spacing-2 In any 'eyent; iiJW'lli 'Jbeappreciated' that witha structure such.,asehassbeenashowmin Figs 16, membee183 maybepotentializediforrforward:projection in a manner sueh'as hasbeennheretofore: outlinedi With" the medicament chamber filled, and themember 183 released for projection, the latter will move forward underthe full forceof spring. ISsltWhichzissnow'under"a maximurrr conditionoftensions. Due tmtheafactithat 'the'saek 186'is filled with liquidtheroutlet oi its"nozzlmis restrictedj itis apparent thatinternai-pressure will b'e iinmedi-atelybuilt-up under the foregoingcircumstances. Such internal or back pressure will cause the base of thesack to bear against plunger 188. Due to the fact that the latter isurged in an outward direction merely by the relatively weak spring 193,any excessive pressures within the medicament chamber will result in rod188 moving rearwardly thus forcing the brake material 191 into operativeengagement with the inner face of casing 182. The greater the degree ofreaction the more intimate will be the engagement between the brakingmaterial and the inner face of the casing. Therefore, under thesecircumstances, the force with which member 183 is projected will bediminished. Conversely, as the pressure within the medicament chamberdiminishes, the braking action will also diminish because rod 188 underthe influence of spring 193 will move outwardly. This relationship ofthe parts may be adjusted with nicety by shifting screw 194 to tensionspring 193 to a greater or lesser extent.

Now considering the values which may be incorporated in the assembly asshown in Fig. 16, it will be assumed that the maximum injection pressuredesired within chamber 186 is 2,000 pounds per square inch. Ignoring allquestion of frictional losses, the main spring 184 will, under thesecircumstances, be preloaded to a value of substantially 220.8 pounds.With spring 184 fully compressed, it may have a thrust value ofsubstantially 331.2 pounds. In the apparatus under consideration it willbe assumed that to assure such complete compression a /2 inch shiftinwardly of the main spring will be resorted to. It will also be assumedthat the plunger assembly 187-188 has a /8 inch diameter. Under thesecircumstances, the minimum thrust exerted by main spring 184 will, asaforebrought out equal 220.8 pounds on the plunger. With the area of thelatter this will equal a pressure of 2,000 pounds per square inch with-1 in the medicament chamber. Thus, the excess force which is to beregulated by the brake structure will be the difference between themaximum thrust of the main spring (331.2 pounds) and the minimum thrustexerted by that member (220.8 pounds). This will represent a maximumdifferential of 110.4 pounds which, at the end of the stroke will havediminished to zero. With the injection pressure commencing at 2,000pounds to the square inch plus the amount of pressure required toovercome the frictional resistance of the parts, it is apparent that ifplunger 188 has a $1 inch overall diameter and due to the cam surfaces189 has a ten to one mechanical advantage on the brake elements or shoes191, then each pound of pressure over the optimum of 2,000 pounds willapply a .276 pound force on the brake shoe. For example, 2,100 poundsper square inch might impart (with properly related surfaces) 27.6pounds force on the braking units. If the load provided by spring 193 is54.2 pounds on internal plunger 188, the latter will just support a2,000 pounds per square inch medicament pressure. As is apparent, theforegoing figures are merely illustrative. By varying the ratiosinvolved, greater or lesser force might be achieved through the use of aspring 184 or other mtive force of the same value. Likewise, a springwhich exerts a greater or lesser thrust might be utilized. Thesevariations together with numerous manners of applying the desiredbraking action will be obvious to a person possessing the necessarymechanical skill.

Thus, among others, the several objects of the invention as specificallyaforenoted are achieved. Obviously numerous changes in construction andrearrangement of the parts might be resorted to without departing fromthe spirit of the invention as defined by the claims.

I claim:

1. A hypodermic injection apparatus including a body providing anampule-receiving chamber, a flexible invertible solution-containing cupwithin the same, means for causing the base of said cup to be shiftedtowards the cup lip to invert the side walls thereof upon one anotherand a lining interposed between the face of said chamber and the cupside walls, said lining comprising a layer of compressively displaceablematerial yielding within the zone of the cup as the latter inverts andexpands radially to press against the adjacent face of said layer and tocorrespondingly constrict the same to the rear of said cup base as thelatter shifts towards the cup lip.

2. A hypodermic injection apparatus including in combination a tubularbody, mounting means adjacent one end of said body for retaining amedicament chamber-defining element in association therewith, a membermovable within said body and having a part projectible towards saidelement to expel medicament therefrom, said member providing a spacecharged with expansive fluid under pressure, a flexible diaphragmcarried by said member and extendable into said space to provide apressure accumulator structure, a cap closing the opposite end of saidbody, a stem having threaded engagement with said cap and extendingbeyond the outer and inner faces thereof, means secured to said stem ata point beyond the outer cap face whereby said stem may be turned, aunit having threaded engagement with said stem at a point within saidbody and connected to said diaphragm to extend the latter into saidmember to increase the expansive force of said accumulator structure andmeans for releasing said member for movement.

3. A hypodermic injection apparatus including in combination a tubularbody, mounting means adjacent one end of said body for retaining amedicament chamber-defining element in association therewith, a membermovable within said body and having a part projectible towards saidelement to expel medicament therefrom, said member providing a spacecharged with expansive fluid under pressure, a flexible diaphragmcarried by said member and extendable into said space to provide apressure accumulator structure, a cap closing the opposite end of saidbody, a stem having threaded engagement with said cap and extendingbeyond the outer and inner faces thereof, means secured to said stem ata point beyond the outer cap face whereby said stem may be turned, aunit having threaded engagement with said stem at a point within saidbody and connected to said diaphragm to extend the latter into saidmember to increase the expansive force of said accumulator structure, aprojecting part carried by said member and a manually releasable latchcarried by said body and cooperable with said part to releasably retainthe latter and said member against movement.

4. A hypodermic injection apparatus including in combination a tubularbody, mounting means adjacent one end of said body for retaining amedicament chamber-defining element in association therewith, a membermoveable within said body and having a part projectible towards saidelement to expel medicament therefrom, said member providing a spacecharged with expansive fluid under pressure, a flexible diaphragmcarried by said member and extendable into said space to provide apressure accumulator structure, a cap closing the opposite end of saidbody, a stem having threaded engagement with said cap and extendingbeyond the outer and inner faces thereof, means secured to said stem ata point beyond the outer cap face whereby said stem may be turned, aunit having threaded engagement with said stem at a point within saidbody and connected to said diaphragm to extend the latter into saidmember to increase the expansive force of said accumulator structure,said member presenting an open rear end, said unit being moveabletowards the interior of said member through said rear end and means forreleasing said member for movement.

5. A hypodermic injection apparatus including in combination a hollowbody providing adjacent one of its ends a chamber to receive amedicament-containing ampule, a hollow piston member reciprocal Withinsaid body, a plunger at one end of said member and projectible into saidchamber to cause expulsion of medicament therefrom, a force-compoundingmeans movably supported With respect to said body and extending adjacentits opposite end, means within said body and operatively connected tosaid force-compounding means to be pro jected thereby into the interiorof said hollow piston member, means forming a part of said apparatusincluding said hollow piston and the means projectible into the interiorthereof to provide a pressure accumulator which upon expansion causesprojection of said piston member and plunger and releasable restrainingmeans carried by said body and engaging said member to normally preventprojection of said plunger.

6. A hypodermic injection apparatus according to claim 5 and in whichbraking means cooperates with said plunger to limit its speed ofprojection thereof, said braking means comprising a normally retractedelement shiftable with respect to and carried With said plunger, saidelement being shiftable into engagement with a surface fixed withrespect to said body to efiect a braking action and means connectingsaid plunger and element to cause such shifting of the latter.

7.- A hypodermic injection apparatus as defined in claim 5, saidpressure accumulator comprising a spring under compression and meansconnecting said pressureincreasing means With said spring.

8. A hypodermic injection apparatus as defined in 14 claim 5, saidpressure accumulator comprising a space embraced within said pistonplunger and filled with a compressed fluid and said pressure-increasingmeans comprising a member projectible into said space to furthercompress such fluid.

9. A hypodermic injection apparatus as defined in claim 5, saidmedicament chamber comprising a cupshaped flexible member, the base ofwhich is acted upon by said plunger, means for securing the edge zone ofsaid member against movement with respect to said body and said plungercausing the side Walls of said member to invert upon themselves as saidplunger acts to shift the base of the same towards said edge zone.

10. A hypodermic injection device as defined in claim 5, saidpiston-retaining means comprising a latch manually shiftable to releasesaid piston for projection, a carriage movably supported by said bodyand mounting said latch and means for normally preventing movement ofsaid carriage with respect to said body.

References Qited in the file of this patent UNITED STATES PATENTS798,093 Dean Aug. 29, 1905 2,221,739 Reiter Nov. 12, 1940 2,322,244Lockhart June 22, 1943 2,322,245 Loekhart June 22, 1943 2,380,534Loclzhart July 21, 1945 2,398,544 Lockhart Apr. 16, 1946 FOREIGN PATENTS505,931 France May 17, 1920

